while and you know, the toll that this takes on a family is real. so he knew enough to know that this wasn't just a sure, honey, whatever you want. >> reporter: if you had said no, we can't do this, would we not be sitting here today. >> we would not, that's why i couldn't say no. >> reporter: her brother craig robinson remembers then-senator obama enlisted him to help sell her on the idea to convince him to run for president. >> he said i think i'll take a run at the presidency, i was like what? if you talked to your wife about in? he was like, no, he says to me, you got to do me favor, you got to talk to her because she's not going to go for it. i was like, you're right, darn right she's not going to go for it. >> reporter: craig tells me -- >> yeah. >> reporter: -- your husband was outright nervous to tell you that he wanted to run for president. is he a little bit intimidated, a little bit afraid of you, do you think. >> no, not at all.